AB1277 POOR LONG-TERM OUTCOMES AND SUBSTANTIAL BURDEN OF COMORBIDITIES IN EUROPEAN PATIENTS WITH DERMATOMYOSITIS/POLYMYOSITIS: RESULTS FROM A SYSTEMATIC LITERATURE REVIEW
Authors: J. Vencovský, K. Pisarczyk, R. Leff, E. Park, K. Palaniswamy, L. Long
Journal: Annals of the Rheumatic Diseases (2022)

Background Dermatomyositis (DM) and polymyositis (PM) are rare heterogenous systemic autoimmune disorders of the skin, muscles and other organs that may have a devastating impact on patients’ lives. Despite various therapies used in clinical practice, a notable proportion of patients seem not to achieve sustainable remission. There is a need to better understand long-term outcomes and comorbidities in patients with DM/PM in Europe. Objectives To systematically review and summarize evidence on clinical burden of disease in patients with DM/PM in Europe. Methods A systematic literature review (SLR) was conducted in MEDLINE and Embase databases to identify studies in children and adults with DM/PM, published in the English language between 2011 and 2021. Primary studies enrolling 10 or more patients were included, irrespective of country or region. Each eligible article was independently reviewed by two reviewers. The title and study abstracts were reviewed to assess eligibility for full-text review. The current abstract summarizes SLR results on the long-term outcomes and comorbidities in patients with DM/PM in Europe. Results A total of 2,967 non-duplicated publications were retrieved from medical databases and analyzed against pre-defined study selection criteria. There were 2,574 records excluded at title and abstract screening. Remaining 393 records were analyzed in the full text with 208 papers considered relevant. Additional 21 papers were identified from searching reference list of relevant studies and conference proceedings. In total, 222 studies (229 publications) were included in data abstraction. Among 43 studies conducted across 14 European countries, 23 studies evaluated long-term outcomes of disease and burden of comorbidities. There were 14 longitudinal cohort studies, 7 cross-sectional analyses and 2 case-control studies. Only 29-44% of DM/PM adults achieved remission. Between 38% and 62% of adults with DM/PM required at least 3 different medications, suggesting inadequate response to initial and subsequent regimens. During a mean follow-up of 13.9 years, 69% patients with JDM had polycyclic or chronic disease characterized by periods of remission and recurrence or by permanently active disease for more than 2 years after diagnosis. A notable proportion of children (60.4%) showed evidence of damage in at least one body organ and 13-20% of patients had complications such as calcinosis, lipodystrophy, or muscle atrophy. Adults with DM/PM often suffered from interstitial lung disease (16-66%), serious infections leading to hospitalization or death (21-26.7%), and cardiovascular disorders (CVDs) (19-71%). Compared to age and gender matched controls without DM, patients with DM had 16-times higher risk of venous thromboembolism (HR=16.44, 95% CI: 7.54-35.86). Incidence of coronary heart disease, hemorrhagic stroke, or ischemic stroke during 10-year follow-up was approximately 1.5- to 2-times higher in DM/PM adults relative to general population. Multiple studies reported high rates of any malignancy in DM adults (7.5-33%) and in PM adults (8-11.7%). During approximately 24,000 patient-years of follow-up, adults with DM/PM had more than 4-times higher incidence of lung cancer compared to general population that also was one of the highest incidences among multiple other autoimmune diseases. Long-term prognosis in DM/PM was poor with 20-year survival below 70%. The most common causes of deaths were pulmonary-related, malignancies, and cardiac complications. Mortality due to lung cancer was more than 4-times higher than in general population (standardized mortality ratio=4.17, 95% CI: 3.03-5.60). Conclusion European patients with DM/PM suffer from substantial burden of comorbidities including serious infections, malignancies and CVDs that lead to poor long-term outcomes. A notable proportion of adult and juvenile patients do not achieve sustainable remission or experience relapse indicating high unmet need. Disclosure of Interests Jiří Vencovský Speakers bureau: Abbvie, Biogen, Boehringer, Eli Lilly, Gilead, MSD, Novartis, Pfizer, Roche, Sanofi, UCB, Werfen, Consultant of: Abbvie, Argenx, Boehringer, Eli Lilly, Gilead, Octapharma, Pfizer, UCB, Grant/research support from: Abbvie, Konrad Pisarczyk Consultant of: Kezar Life Sciences, Richard Leff Shareholder of: Kezar Life Sciences, Consultant of: Kezar Life Sciences, Eunmi Park Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences, Kiruthi Palaniswamy Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences, Li Long Shareholder of: Kezar Life Sciences, Employee of: Kezar Life Sciences.